基于能量法的悬臂金属拱型波纹屋面的剪力滞分析

SHEAR LAG ANALYSIS OF THE CANTILEVER ARCHED CORRUGATED METAL ROOF BASED ON ENERGY METHOD

金属拱型波纹屋面是一种新型空间薄壁钢结构,在工程中常作为悬臂结构出现。由于波纹的存在对刚度和抗弯性能有较大的提高,研究其作为悬臂结构是一个新的探索。对单个波纹拱进行分析,应用变分法的最小势能原理对金属波纹拱悬臂结构的剪滞效应进行分析,建立悬挑结构的剪滞翘曲位移公式,给出剪力滞影响下的截面正应力和剪应力公式,并对悬臂结构形式进行算例分析。计算结果表明:剪滞附加正应力、剪应力在距固端0.07梁长处最大,与按初等梁理论计算应力值相比较,剪滞影响最大不超过4%。

Arched corrugated metal roof is a new type of space thin-walled steel structure and commonly occurs as a cantilever structure in engineering.As the existence of the ripple,the stiffness and bending performance has greatly improved.The research as a cantilever structure is a new exploration.In this paper,a single corrugated arch is analysed.By the application of variations of the minimum potential energy principle,the shear lag effect of the corrugated metal arch cantilever structure is analysed.A cantilevered structure of shear-lag warping displacement formula is established.The cross-section normal stress and shear stress formula under the influence of shear lag effect are given.A cantilever structure is analysed,the results show that additional normal stress and shear stress of shear lag are largest away from the fixed end of the beam by 0.07 times and compared with elementary beam theory,the impact of shear lag is no more than 4%.